Not even the most successful founders can do everything themselves. Bill Gates is one of the richest people in the world, but he admits that hiring and managing employees gives him more anxiety at work than anything else.

Billionaires like Gates hate bad hires. They want to onboard people who can grow their businesses and outsmart their competitors, not lazy or incompetent people who waste their time. Given the success of Gates and others in his tax bracket, billionaires clearly know how to separate the real thing from pretenders.

Small businesses without billions in revenue really need to nail every hire. While a billionaire can take the hit of a bad employee and move on, the wrong hire at the wrong time can tank a promising startup. Founders, more than anyone, need to hire the right person on the first try. Use these interview questions from billionaires like Gates to weed out the fakes and identify the people who have what it takes to help your business soar.

“Who is the best in the world at what you do? Who influences you?” -- Drew Houston, founder of Dropbox

As the founder of Dropbox, Drew Houston made dozens of critical hires during his rapid climb to the top. He prefers to take a hard line of questioning with candidates to find people who truly love what they do.

According to Houston, this question helps him find “people who are always trying to be better and are obsessed with what separates great from good.” Founders of startups need people who are not only good at what they do, but are also committed to learning new things. By asking candidates about the people they admire, you can see who cares about the work and who only clocks in for the paycheck.

Steve Cohen made his money as an investor in both assets and people. He likes to ask prospective employees about the risks they’ve taken that have helped them break through barriers or discover new things.

“I want to hear something unique,” he said. “Something entrepreneurial. Because this is a risk-taking business to some degree. And you want people who are able to take a risk in a controlled way, but not afraid to.”

One of Cohen’s biggest risks was a hire he made in 2013. He brought in Doug Haynes, ex-CIA and McKinsey executive, to be the president of Point72, his investment company. Haynes didn’t have the industry experience Cohen preferred, but he admired Haynes’ ability to tackle problems from new perspectives.

“Where are you?” -- Elon Musk, founder of Tesla

Elon Musk does things a little differently. His preferred question goes like this:

“You’re standing on the surface of the Earth. You walk one mile south, one mile west and one mile north. You end up exactly where you started. Where are you?”

Riddles like Musk’s are less about judging whether candidates know the answers to odd questions and more about seeing how they think on their feet. Google famously used to ask weird questions about why manhole covers are round and how to create an evacuation plan for the city of San Francisco. Questions that put candidates in unusual thought spaces provide opportunities for humor, problem-solving and a little creative showboating.

Not every life accomplishment fits neatly on one page. Richard Branson understands that. In his book, "The Virgin Way," Branson reminds readers that if applications told the whole story, businesses wouldn’t need to conduct interviews at all.

Candidates can answer this question in a variety of ways. Some might brag about personal side projects, while others might highlight unique educational backgrounds or volunteer work. The “right” answer in this case would be one that showcases positive traits like tenacity, empathy or ingenuity.

“What do you think of this?” -- Steve Jobs, founder of Apple

Steve Jobs famously never delegated his hiring process. Over his career, he interviewed more than 5,000 applicants. Jobs quickly realized he preferred people who did things over people whose only skills were in management, so he devised a unique test for potential applicants.

During interviews, Jobs and his team presented candidates with prototypes of Apple products and gauged their reactions. People who got excited about the potential of the technology and started asking questions passed the test. Jobs wanted his employees to feel compelled to create and explore, a philosophy that inspired everything from Apple’s interview process to its commercials.

Billionaires don’t have time to waste on bad hires. They want people who can come in and start making a difference on the first day. For owners of small businesses, the stakes are even higher. Only by weeding out the wrong fits and identifying the real innovators can founders create stronger teams.

More from Entrepreneur

New York Times bestselling author Nicole Lapin can help you pitch your brand to press and strengthen your media training.